1. Field of the Invention
The present invention relates to curable compositions comprising polyepoxides and polyacid agents. More specifically, the present invention relates to composite coatings which are color plus clear coatings wherein the clear top coats are powder coatings. The invention also relates to the process for preparing color plus clear coated articles and to the coated articles themselves.
2. Brief Description of the Prior Art
Color plus clear coatings involving the application of a colored or pigmented base coat to a substrate followed by the application of a transparent or clear top coat to the base coat are becoming increasingly popular as original finishes for automobiles. The color plus clear coatings have outstanding appearance, manifesting in gloss and distinctness of image (DOI). The nature of the clear coat is particularly important for these properties.
Also, the nature of the base coats can be important for these properties. Generally, base coats containing the likes of melamines that produce volatile emissions during cure can adversely affect the appearance of the color plus clear coatings. In the instance of powder coatings, the emissions and associated problems can become more pronounced. This is because powder coatings are generally baked to relatively high temperatures at which volatile emissions are more readily produced.
It is an object of the present invention to provide the means for avoiding problems of appearance in color plus clear coatings, particularly those involving powder coatings.